diff --git a/ChangeLog b/ChangeLog
index 8449c57d4d..60c84485d2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Aug  4 01:28:19 2006  Tanaka Akira  <akr@fsij.org>
+
+	* io.c (io_reopen): STDERR.reopen(File.open("/dev/null", "w")) should
+	  not fclose stderr.
+
 Thu Aug  3 15:16:44 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* range.c (range_include): should always call Enumerable#include?
diff --git a/io.c b/io.c
index 87435a3e38..0749d0fb45 100644
--- a/io.c
+++ b/io.c
@@ -3412,6 +3412,7 @@ io_reopen(VALUE io, VALUE nfile)
     OpenFile *fptr, *orig;
     int fd, fd2;
     off_t pos = 0;
+    int fptr_is_prep_stdio;
 
     nfile = rb_io_get_io(nfile);
     if (rb_safe_level() >= 4 && (!OBJ_TAINTED(io) || !OBJ_TAINTED(nfile))) {
@@ -3422,7 +3423,8 @@ io_reopen(VALUE io, VALUE nfile)
 
     if (fptr == orig) return io;
 #if !defined __CYGWIN__
-    if (IS_PREP_STDIO(fptr)) {
+    fptr_is_prep_stdio = IS_PREP_STDIO(fptr);
+    if (fptr_is_prep_stdio) {
 	if (((fptr->mode & FMODE_READWRITE) & (orig->mode & FMODE_READWRITE)) !=
             (fptr->mode & FMODE_READWRITE)) {
 	    rb_raise(rb_eArgError,
@@ -3455,7 +3457,7 @@ io_reopen(VALUE io, VALUE nfile)
     fd2 = orig->fd;
     if (fd != fd2) {
 #if !defined __CYGWIN__
-	if (IS_PREP_STDIO(fptr)) {
+	if (fptr_is_prep_stdio) {
 	    /* need to keep stdio objects */
 	    if (dup2(fd2, fd) < 0)
 		rb_sys_fail(orig->path);